[FIX, INTERNAL] Fixes issue with bit scan reverse and forward for 32 bit systems.

Fixes bitScanReverse and bitScanForward for different word sizes.
Adds bitwise xor functor.
Adds xor operator for bit compressed tuples.
Adds general bit operators for packed bool strings.
Adds test for empty strings in bitScanForward, bitScanReverse and transform function for packed bool strings.
Updates tests for empty packed bool strings.
[FIX] Adds windows intrinsics for bitScanReverse and bitScanForward.

Adds platform independent implementation for bitScanReverse and bitScanForward.
[INTERNAL, API] Adds windows intrinsics and a generic implementation for bitScanReverse and bitScanForward.

Adds platform independent implementation for bitScanReverse and bitScanForward.
Changes result value for bit scan reverse and bit scan forward if no bit is set to length of the packed string.
Merge branch 'feature/fix_packed_string_bit_twiddling' of https://github.com/rrahn/seqan into feature/fix_packed_string_bit_twiddling

Conflicts:
	core/include/seqan/misc/misc_bit_twiddling.h
[NOP] Updates some comments.
[INTERNAL] Adds  generic fall back methods for bsf and bsr.

Adds missing static.
Enhances method to compute 64 bit bsf and bsr for 32 bit windows platforms.
Merge branch 'feature/fix_packed_string_bit_twiddling' into develop

Conflicts:
	core/include/seqan/misc/misc_bit_twiddling.h
Merge pull request #226 from rrahn/develop

[FIX, INTERNAL] Fixes issue with bit scan reverse and forward for 32 bit...