Fixed Makefile issue by moving the -lz LDFLAG to after the -o argument

Compiling with the default makefile caused this error on FARM2:

~/temp/seqqs$ make
gcc -Wall -pedantic -DVERSION=0.01 -std=gnu99 -O3 -c seqqs.c -o seqqs.o
gcc -Wall -pedantic -DVERSION=0.01 -std=gnu99 -O3 -lz seqqs.o -o seqqs
seqqs.o: In function `ks_getuntil2.constprop.5':
seqqs.c:(.text+0x5c): undefined reference to `gzread'
seqqs.o: In function `kseq_read':
seqqs.c:(.text+0x2b7): undefined reference to `gzread'
seqqs.c:(.text+0x44b): undefined reference to `gzread'
seqqs.c:(.text+0x48f): undefined reference to `gzread'
seqqs.c:(.text+0x5f8): undefined reference to `gzread'
seqqs.o: In function `main':
seqqs.c:(.text.startup+0x1f0): undefined reference to `gzdopen'
seqqs.c:(.text.startup+0x684): undefined reference to `gzopen'
seqqs.c:(.text.startup+0x6e3): undefined reference to `gzclose'
collect2: error: ld returned 1 exit status
make: *** [seqqs] Error 1

I fixed it by moving the LDFLAGS argument after the -o output.