Added initial software emulation for single-stepping.
This requires computing the next address for each instruction,
and planting a breakpoint there. The next-address computation
is incomplete at this time, but should work for basic debugging.
See https://bugs.eclipse.org/bugs/show_bug.cgi?id=404253
for details and discussion.

Change-Id: I4564ddf7adb9316060b37dd6e8ffc26a3b797b27
Signed-off-by: Martin Oberhuber <martin.oberhuber@windriver.com>

… and subtraction instructions

…ction is called before line numbers info is loaded

…mode.

In order to get the list of services available after a redirect of the connection, two new commands are added: redirect and services.

…ailable when ENABLE_ELF = 0

…h does not exist

… mdep.c to other OSes

Add support of ISA, Simplified, Pseudo and OpcodeValue parameters:
 - "ISA" : <string>
    The name of the instruction set architecture.
 - Simplified" : <boolean>
    If true, simplified mnemonics are specified.
 - "PseudoInstructions" : <boolean>
    If true, pseudo-instructions are requested.
 - "OpcodeValue" : <boolean>
    If true, the instruction code byte values are returned.

… session

Fixed regression issue where signal mask was not correctly set for threads
created by a debugged process. Those threads should have inherited the
signal mask of the creator/process but it was no longer the case.

…ith separate debug info file

… functions

…t provide LineNumber service, it should return empty list of areas instead

…lue and DW_OP_GNU_regval_type