[TASK][DOC] (libstfinv): provide description of parameter string syntax

src/libs/libstfinv/usage/stfinvany_description_usage.txt

@@ -2,39 +2,32 @@
 # ----------------------------------------------------------------------------
 # This file should address the selection of the different procedures. The
 # overall concept of the library is explained in the base class.
-Available procedures
-====================
-Detailed description
---------------------
+How to control the procedure
+----------------------------
+A specific procedure is selected by passing a parameter string. This string
+may further contain parameters to control the way the procedure will be
+applied.
 
-How to construct parameter strings
-----------------------------------
-A specific engine is selected by passing a parameter string.
-This parameter string may further contain parameters to control
-the execution mode of the engine.
-The parameter string starts with an ID-sequence identifying
-the desired engine. See the list below for available engines.
-In the parameter string the ID-sequence is terminated by a
-colon (:).
-After selecting the desired engine, the interface function
-strips of the ID-sequence as well as the colon from the
-parameter string and initializes the engine and passes the
-remainder of the parameter string to the engine. This
-remainder may consist of several control parameters being
-separated by colons (:). Each control parameter may just be
-a flag (switch to turn an option on) or may come along with
-a parameter value. The value of the parameter is separated
-by an equal sign (=).
+The parameter string starts with an ID-sequence identifying the desired
+procedure. See the list available procedures for ID strings. In the parameter
+string the ID-sequence is terminated by a colon (:).
+
+After selecting the desired procedure, the interface function strips off the
+ID-sequence as well as the first colon from the parameter string. The
+remainder may consist of several control parameters being separated by colons
+(:). Each control parameter may just be a flag (switch to turn on an option)
+or may come along with a parameter value. The value is separated from the
+parameter by an equal sign (=).
 
 Examples:
-- To select Fourier domain least squares and shift
-  the returned source correction filter wavelet by 0.4s and
-  switch on verbose mode, pass the following parameter string:
+- To select Fourier domain least squares and shift the returned source
+  correction filter wavelet by 0.4s and switch on verbose mode, pass the
+  following parameter string:
     fdlsq:tshift=0.4:verbose
-- To select the identity engine and to switch on debug level 4:
+- To select the identity procedure and switch on debug level 4:
     ident:DEBUG=4
-- To select Fourier domain least squares, apply offset
-  dependent weights and use a power of two to speed up the FFT:
+- To select Fourier domain least squares, apply offset dependent weights and
+  use a power of two to speed up the FFT:
     fdlsq:pow2:exp=1.4
 #
 # ----- END OF stfinvany_description_usage.txt ----- 

src/libs/libstfinv/usage/stfinvany_summary_usage.txt

 # this is <stfinvany_summary_usage.txt>
 # ----------------------------------------------------------------------------
 #
-Syntax for parameter strings
+How to control the procedure
 ----------------------------
 Procedures can be selected by passing the procedures ID together with options
-an parameters controlling the algorithm used for the procedure.
+an parameters controlling the algorithm used.
 
 Syntax of parameter string:
   ID:option:option=value:option=value