Merge STF_SH into development

INVMAT - > FORWARD_ONLY
INVMAT1 - > PARAMETERIZATION

Adding a few gitignore files to smooth the GIT workflow

! IFOS -> IFOS2D !
- New make targes is IFOS2D
- Generated binary is IFOS2D

Adding 2D to IFOS to indicate, that it is our 2D FWI Code.

Renaming of observed seismograms:
SEIS_FILE_z.su -> SEIS_FILE_vz.su
SEIS_FILE_x.su -> SEIS_FILE_vx.su
SEIS_FILE_y.su -> SEIS_FILE_vy.su

Either rename your observed data, or (if synthetic) rerun forward modeling, so IFOS will create observed data, which is correctly named.

Renaming:
QUELLART     ->  SOURCE_SHAPE
QUELLTYP     ->  SOURCE_TYPE
QUELLTYPB   ->  ADJOINT_TYPE
DAMPING       ->  VPPML

! This commit renames DENISE to IFOS !
Keep care and update all of your self written shell scripts etc.
The make target is 'IFOS' (capital letters).
The resulting binary is called 'IFOS' as well.

Changed output of L2 to STDOUT if WAVETYPE != 3

Separate waterlevel for SH-waves && new joint function which takes the mean without normalization.